RU2315584C1 - Intravenous anti-embolic filter - Google Patents

Abstract

FIELD: medical equipment; surgical instruments.

SUBSTANCE: intravenous anti-embolic filter can be used for catching grums. Filter has catheter in form of hollow tube. There are thread-like members at one end of tube; members are oriented radial to hold grum. Catheter is also provided with flat radial directed members and with support member in form of ring made for rest of its external surface against wall of vein. Ring is mounted with concentricity to tube at one end of tube; ring is connected with tube by mentioned radial directed thread-like members. Flat radial oriented members are attached to external surface of tube in front of ring at side of other end of tube; flat members have cutting edge along their lengths. Cutting edge is turned to other end of tube, which end is closed at its edge. Through openings are made along length of tube I its sidewall in part disposed from closed edge to flat members provided with cutting edge. Anti-embolic device prevents migration of thrombotic masses and helps to crush the mass to separate components.

EFFECT: higher reliability of catching grums; higher efficiency of grum crushing; provision of normal blood current in vein.

1 dwg

Description

The invention relates to the field of medical equipment, namely to surgical instruments for trapping blood clots, in particular, the invention relates to the construction of an intravenous anti-embolic device that impedes the migration of thrombotic masses and allows this mass to be divided into separate components.

Sudden disruption of blood flow through the great arteries with a threat to the viability of the tissues they feed occurs as a result of thrombosis, embolism or damage. Embolism more often than others leads to acute arterial occlusion. By embolism is meant the entry into the arterial bed of a foreign body leading to its blockage. Most often, emboli are pieces of an organized blood clot, accumulations of fat or gas, and other foreign bodies (plastic tubes, metal objects, bullets). The main sources of peripheral artery embolism are currently considered to be heart disease (95% of all cases). At the same time, more than half of them are atherosclerotic cardiopathies: myocardial infarction, post-infarction cardiosclerosis, heart aneurysms. Acquired heart disease is 40-43% and congenital malformations are 1-2%. With atherosclerotic cardiopathies, a blood clot is usually localized in the left ventricle, and with heart defects in the left atrium or its ear. Of non-cardiac sources of embolism, the first place is occupied by aortic aneurysm (34%), then subclavian artery aneurysm, venous thrombosis of the large circle of circulation (with defects of the heart walls), pneumonia, lung tumors.

To prevent clots from entering vital organs, such as the heart, devices such as filters are used that are installed on the path of movement through the bloodstream of a clot to stop this clot and, in some cases, to crush it into dispersed fragments.

Known intravenous filter made of two cones connected by a common rod and formed by elastic threads with free ends bent outward on one of the cones. The free ends of the other cone are divided into two parts, opposite curved from the axis of the filter, while the vertices of the cones are facing one another (RU No. 20402278, A61M 1/34, A61B 2/06, 1995).

The disadvantage of this filter is that when it is installed, the fixation cone may be skewed, since its filaments exit first and the threads of the centering cone into the second, as a result of which blood clots are not caught, but slip between them.

Known intravenous filter designed to block the inferior vena cava and create a barrier against embolus migration (WO, application No. 0270432, A61F 2/02, 1988). It has a thread-like housing, extended at one end by a first filter, consisting of numerous flexible diverging threads in the form of a cone, which are held at an even distance around the circle relative to each other. The free end of each thread is bent outward so as to form a point for engagement. The other end of the housing ends with a stabilizer serving as a second filter consisting of numerous flexible threads diverging around the housing. The threads are held at a uniform distance around the circumference relative to each other and are rejected at a certain angle with respect to the threads of the cone forming the first filter. The free ends of these threads are bent inward. Both ends are turned in one direction.

However, the known device has several significant disadvantages.

When installing, it is possible to skew the filter coming out of the catheter first, the threads of which serve simultaneously to engage the vessel walls, since the threads of the filter intended for centering come out first. As a result of distortion, blood clots slip past the filter. In addition, when the centering cone exits the catheter, bending of the vein is possible. At the bend, the laminar flow of blood is disturbed, which can lead to blood clots.

Known intravenous filter containing a filter element of two cones facing the vertices in one direction and consisting of numerous diverging flexible threads, the free ends of which in one cone are bent outward and bent inward in the other, while the filter is additionally equipped with means for installing the filter element, consisting of a catheter and a pusher placed in it with the possibility of movement, the working end of which is made in the form of a V-shaped bend perpendicular to the axis, and the cone strands with internal bent the free ends have a longer length and a smaller bending radius at the apex than the cone threads with the free ends bent outward, which are split, while the cones are aligned at the apex so that the threads of one cone are evenly spaced around the circumference between the threads of another cone and are rigidly connected by a bushing, equipped with a round-shaped hook at the opposite end that is meshed with a V-bend, the size of which is less than the inner diameter of the hook and less than the inner diameter of the catheter in length (RU No. 2103015, А61М 1 / 34, A61B 2/01, publ. 01/27/1998).

The disadvantage of this filter is that its threads are located in each row with an offset to ensure crushing of the clot due to its pressing by blood pressure to these threads. This method of crushing is not always effective, since it depends on the structure of the bunch itself. In some cases, such crushing is not possible at all, which leads to the closure of the vein canal.

The present invention is directed to solving the technical problem of creating an intravenous filter that provides more reliable capture of blood clots and their crushing into dispersed components while ensuring normal blood flow in the vein.

The technical result achieved in this case is to increase the efficiency of the filter and expand its capabilities while providing obstacles to the movement of blood clots and foreign bodies in the bloodstream.

The specified technical result is achieved by the fact that an intravenous anti-embolic filter containing a catheter, which is a hollow tube carrying threadlike elements at one end, radially directed to hold the clot, is equipped with a supporting element in the form of a ring made with the possibility of supporting the outer surface on the vein walls, mounted concentrically to the tube at one at its end, to which this ring is connected by said radially directed threadlike elements and flat radially directed elements mounted on the outer surface of the tube in front of the ring from the side of the other end of the tube and made with a cutting edge along the length of the elements facing the other end of the tube, made closed from the end, and along the length of the tube in its side wall in the section from the closed end to through elements are made of flat elements with a cutting edge.

Using the invention allows to obtain the following technical result.

- An intravenous filter reliably traps blood clots, prevents the risk of them entering the heart and thereby reduces the likelihood of death.

- The possibility of arranging the filter cutting elements against the blood flow provides better crushing and erosion of the emboli by the blood flow.

- Ensures accurate installation of the filter element in a given section of the veins, which improves the efficiency of the operation.

The use of an intravenous filter is safe for the patient, it provides atraumatic insertion, installation and removal of the filter element.

These signs are significant and interconnected with the formation of a stable set of essential features sufficient to obtain the desired technical result.

The present invention is illustrated by a specific example of execution, which, however, is not the only possible, but clearly demonstrates the possibility of achieving the desired technical result.

The drawing shows an intravenous filter in the working position.

The intravenous anti-embolic filter contains a catheter, which is a hollow tube 1, equipped with a supporting element in the form of a ring 2, made with the possibility of supporting the outer surface on the walls of the vein. Ring 2 is mounted concentrically to tube 1 at one at its distal end in the direction of blood flow and is connected to this tube at this end by radially directed numerous flexible (may not be flexible, weakly flexible, elastically deformable) divergent threadlike elements 3, serving as a filter to hold the moving downstream of the bunch.

The tube 1 at its other end is closed from the end.

Flat radially directed elements 4 are fixed on the tube, fixed on the outer surface of the tube in front of the ring 2 from the closed end of the tube and are made with a cutting edge 5 along the length of these elements.

The tube along the length in the side wall in the area from the closed end to the flat elements 4 with a cutting edge is made with through holes 6.

The operation of the intravenous filter is as follows.

During surgery, a catheter is inserted into a vein under x-ray television control so that the catheter ring 2 is upstream of the site of the blood clot. If the retention of the ring in the vein is due to the fact that its diameter is slightly larger than the size of the vein, then first expand the vessel, and then enter the catheter with the ring. If antennae or filamentous bursting elements are made on the outer surface of the ring, then the ring is inserted when these antennae are folded, which then straighten and hold the catheter with the ring from movement.

When moving, the clot enters the tube 1, bypasses it and moves towards the ring. On the way, the bunch gets to the cutting edges 5 of the flat elements 4, where under the blood pressure the bunch is cut into components that fall into the ring zone into threadlike elements 3, holding small particles that cannot be crushed, and crushing those particles whose structure allows disperse them. Holes 6 in the tube ensure the safety of blood flow in those cases when the clot is on the elements 4.

The present invention is industrially applicable, as it can be manufactured using technologies for the production of catheters and filters for medical purposes.

Claims (1)

An intravenous anti-embolic filter containing a catheter, consisting of a hollow tube carrying filiform elements at one end, radially directed to hold the clot, characterized in that it is provided with a supporting element in the form of a ring made with the possibility of supporting the outer surface on the walls of a vein mounted concentrically a tube at one end with which this ring is connected by said radially directed threadlike elements and flat radially directed elements fixed on the outer surface of the tube in front of the ring from the side of the other end of the tube and made with a cutting edge along the length of these elements facing the other end of the tube made closed from the end, and along the length of the tube in its side wall in the section from the closed end to the flat elements with through holes are made through holes.